In other words, what if you could deliver a baby boy who'd grow up with the chiseled good looks of the international soccer star David Beckham? Or maybe you'd prefer offspring with the matinee idol visage of Ben Affleck? Or a baby boy who'll one day resemble Duane "The Rock" Johnson?

"It can be the shape of the eyes, the nose, the mouth, any specific feature," said Scott Brown, director of communications at California Cryobank. "It can be the shape of the head. It can be the complexion. It can even be the hairstyle because you're talking about [what] someone looks like. That's what we're going for."

It's a service that's bound to cause confusion over the question, "Who's your daddy?"

At California Cryobank, which has been in business for over 30 years and says it accepts only 1 percent of sperm-donor applicants, members of the staff sift through their long list of anonymous sperm donors. Then they vote to decide which of them are dead ringers for movie stars and athletes. Would-be parents can then pick which celeb they'd like their baby to resemble.

"Right now, the top guys on our list are Paul Walker, who was in 'The Fast and the Furious.' Ben Affleck is very popular. Scott Caan is popular," Brown told "Nightline." "Brett Favre is actually pretty popular. Jeremy Shockey was in the top 10 the last time I checked. It's a pretty wide range of guys."

He also mentioned Greg Grunberg of the TV show "Heroes" among the most popular picks.

Celebrity look-alike sperm may seem superficial, but before you write off the idea, meet 33-year-old Alice Crisci, the California Cryobank client behind it.

"It humanizes the entire experience," she said. "It even brings a little levity to an overwhelming, emotional scary time in a woman's life."

Diagnosed with an aggressive form of breast cancer at just 31, Crisci would lose her breasts and hair and feared that she would lose her chance at motherhood.

Breast Cancer Diagnosis Brings Woman to Freeze Embryos

Before Crisci underwent a mastectomy in April 2008, she decided to have her embryos frozen. She spent around $15,000 to $20,000 in the process.

In the seven days before she began her egg retrieval, she combed through hundreds of potential donors, examining their profiles and nitpicking every last detail to decide who would help create the best baby. But the prospect of picking a faceless donor out of a catalog was overwhelming.

"Typically, clients start with the Web site and they do a search. They'd go through the ethnicity they were looking for, height, weight, eye color, hair color, blood type. You can look at religions, scholastic background, profession," Brown said. "It was all designed to get you as close to the donor without showing you a picture or revealing his true identity because it's an anonymous donor program."

Crisci -- who now runs a nonprofit organization, My Vision, that helps women with breast cancer deal with fertility preservation questions -- was able to narrow it down to her favorites based on things like the donor's height, weight, profession and education. But when she still had trouble deciding how to pick one donor off her short list, Brown and his team came up with an idea for putting "faces" on the anonymous potential fathers she selected.

"One of the things we tried to do was sit down and create lists of celebrities that looked like the donors that Alice had narrowed her choices down to," he said. "It worked really well. She was really happy with it, and it was really helpful in making that decision."

Brown said that was the genesis of the celebrity look-alike service. Since then, it's become the latest trend in designer babies. California Cryobank says its Web site traffic is up some 600 percent in the weeks since the service launched.

But many aren't happy about it. Daniel Sulmasy, a bioethicist at the University of Chicago, likens the celebrity look-alike service to selective breeding -- shopping at the supermarket for the perfect child.

"They're not the only ones who do this sort of thing. In New York City, there's a place that specializes in Scandinavian sperm and they give the parents a card when the child is born that says 'Congratulations, it's a Viking,'" Sulmasy said. "This sort of stuff, while it seems funny, really ought to make us very frightened as we select people who have blond hair, blue eyes, are smarter and taller."

Fertility clinics have long recruited donors based on brains and brawn. But when they concentrate on beauty, like how much the offspring might look like a handsome actor, Sulmasy said there are serious repercussions.

"One of the hidden ethical issues within this approach to genetic engineering is that the people who are already well off, who are wealthy, are going to get the sperm that are going to be more perfect, have the children that are stronger, smarter, faster, more beautiful and be even more advantaged in society -- while the poor, who are already disadvantaged ... have less access to this kind of technology," Sulmasy said.

"We all know that people within our society, people who are better looking, are more likely to get jobs and be better advantaged within society," Sulmasy added. "The gap between the rich and the poor will only grow greater the more we pursue this kind of avenue."

And Sulmasy wonders what should happen if your baby doesn't end up looking like your favorite movie star?

"Maybe the child is supposed to look like Harrison Ford," he said, "and if they come out not looking as someone quite as handsome as Harrison Ford, what does that do to the relationship between the parent and the child? Are they terribly disappointed because it's not perfect? ... Genetics is, even with something like this, a bit of a lottery."

'McLovin,' Steve Urkel, Jon Gosselin All Sperm Donor Look-Alikes

Brown said there are no guarantees.

"We're not promising that your child is going to look like these celebrities. These celebrities' children don't always look like them," he said. "Genetics is a tricky business and all we do is try to humanize and personalize the process and make it as easy for our clients as possible."

The Cryobank is quick to point out that the service is not entirely superficial. Not everyone on their list of donor look-alikes is a hunky leading man.

Remember Christopher Mintz-Plasse, who played the dork "McLovin" in the hit comedy "Superbad"? There's a donor who looks like him. There's also a Steve Urkel. And a Jon Gosselin, too.

"I know there are going to be people out there who think they're trying to make designer babies or trying to do this or that. You should leave it up to God or adopt. Those people don't get it. And I hope they never get it," Crisci said. "And if they do, I hope it's because they know somebody that went through what I went through or because they went through it themselves."

Crisci's embryos remain frozen. But she narrowed her celebrity look-alikes down to one man who actually resembles three stars. She's been told he has a combination of Oscar de la Hoya's complexion, David Cassidy's nose, and the lips and eyes of Freddie Prinze Jr.; a real Hollywood hybrid in the making.

"When I heard him say Freddie Prinze Jr., I actually laughed and said, 'but not his eyebrows, right?'" she said. "It definitely pleases me. Now that they have the entire tool up and running, I probably would have looked for Joey Lawrence because he was my crush since 'Blossom' days."